Most peo­ple don’t under­stand the dif­fer­ence between 95 and 99 per­cent accu­rate. Nine­ty-five per­cent means you get one-in-20 words wrong. That’s just annoy­ing, it’s painful to go back and cor­rect it on your cell phone.

Nine­ty-nine per­cent is game chang­ing. If there’s 99 per­cent, it becomes reli­able. It just works and you use it all the time. So this is not just a four per­cent incre­men­tal improve­ment, this is the dif­fer­ence between peo­ple rarely using it and peo­ple using it all the time.

It’s fas­ci­nat­ing to see how these small num­bers make a huge dif­fer­ence; you might think Google’s 92% accu­rate is only a lit­tle less than Baidu’s 95% accu­rate, but in prac­ti­cal terms there’s a big gulf. And it gives me pause to think about the mon­ey, human resource and com­put­ing pow­er spent on try­ing to make those small huge increas­es in accu­ra­cy.